Handles aria-dropeffect after getting its value from blink.

content/test/data/accessibility/aria/aria-dropeffect-expected-android.txt

Index: content/test/data/accessibility/aria/aria-dropeffect-expected-android.txt
diff --git a/content/test/data/accessibility/aria/aria-dropeffect-expected-android.txt b/content/test/data/accessibility/aria/aria-dropeffect-expected-android.txt
new file mode 100644
index 0000000000000000000000000000000000000000..f168b15f16afb572e8466efa533622db661a595f
--- /dev/null
+++ b/content/test/data/accessibility/aria/aria-dropeffect-expected-android.txt
@@ -0,0 +1,23 @@
+android.webkit.WebView focusable focused scrollable
+    android.widget.ListView collection hierarchical item_count=7 row_count=7
+        android.view.View collection_item name='copy'
+            android.view.View clickable name='•'
+            android.view.View clickable name='copy'
+        android.view.View collection_item name='move' item_index=1 row_index=1
+            android.view.View clickable name='•'
+            android.view.View clickable name='move'
+        android.view.View collection_item name='link' item_index=2 row_index=2
+            android.view.View clickable name='•'
+            android.view.View clickable name='link'
+        android.view.View collection_item name='execute' item_index=3 row_index=3
+            android.view.View clickable name='•'
+            android.view.View clickable name='execute'
+        android.view.View collection_item name='popup' item_index=4 row_index=4
+            android.view.View clickable name='•'
+            android.view.View clickable name='popup'
+        android.view.View collection_item name='none(defalut)' item_index=5 row_index=5
+            android.view.View clickable name='•'
+            android.view.View clickable name='none(defalut)'
+        android.view.View collection_item name='link' item_index=6 row_index=6
+            android.view.View clickable name='•'
+            android.view.View clickable name='link'